abstract: The notion of pluricomplex energy was introduced by U. Cegrell in 1988. Since then it has played an important role in complex Monge-Ampere equations. I present a recent joint work with Do Duc Thai in which we characterize the class of probability measures on a compact Kahler manifold such that the associated Monge-Ampere equation has a solution of finite energy. Such a characterization was previously only known in particular cases.